clear powder on hubs, brakes

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Onder

Onder

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I ve polished my front hub. Would like to clear coat it, powder. Since
the oven is at about 400F, is this any problem with the hub later on and
would it affect the drum true? Assume I remove bearing first of course.
 
Science! Let us know how it works out. Has this finisher done any other motorcycle hubs?
 
Science? Yes, but don't wish to be the experimental victim.
And yes, he has done wheels and hubs but not drum hubs.
 
Onder said:
Science? Yes, but don't wish to be the experimental victim.
And yes, he has done wheels and hubs but not drum hubs.
Click to expand...

I don't know if the 400F will cause the iron to separate some from the aluminum hub. My gut reaction is, no problem. No facts to back it up, just 35 years in the metal trade. Does anyone have a cutaway image of such drum? "Paging L.A.B.." :mrgreen:
 
Well there is that. At 350 you can drop the bearings out of a case easily.
 
Onder said:
Well there is that. At 350 you can drop the bearings out of a case easily.
Click to expand...

The aluminum hub is usually cast around the iron brake drum, ribs may be incorporated to ensure integrity.
 
400F is above a "Precipitation Heat Treatment" temperature (375F) where the structure of aluminum begins to change:

http://www.mlevel3.com/BCIT/heat%20treat.htm

Over time, it actually strengthens the aluminum but at the same time may make it more brittle. Still, it is well below full anneal temperatures of 900F
 
My only direct experience is powder coating iron hubs which work well, but I do remember reading a post where an aluminium hub was powder coated and the coating cracked within a few miles of use due to the aluminium having less rigidity than iron. Based on this I have never tried it.
 
Lacking firm data, Id say a bit iffy to try. The down side greater than the possible upside.
Think it will stay uncoated polished alloy and Ill simply have to attend to it regularly.
 
I do my own polishing. I have some parts I polished 20 years ago on a buffing wheel followed by Simichrome or Autosol. They are still shiny without any extra coating. I have some clear coat powder painted on some other parts that have started to yellow or peal.
 
A lot of modern bike parts come in black or silver finishes = powdercoat. ??

They seem pretty tough, is the clear stuff as good ?
 
I have heard of hubs that cracked in service after powdering. Whether the powder guy was on the stick or not I do not know but after having the hubs polished and turned the worry is significant unless somebody chimes in otherwise.
 
I use Glisten for hubs and aluminum parts. It is made by Por 15 and sticks to a polished surface with no problem. Slow to dry but hard as a rock. Jim
 
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